Bulletin of the Seismological Society of America; April 2003; v. 93; no. 2;
p. 694-712; DOI: 10.1785/0120000831
© 2003 Seismological Society of America
Dynamic Response of Two Historical Monuments in Istanbul Deduced from the Recordings of Kocaeli and Düzce Earthquakes
Eser Durukal,
Serkan Cimilli and
Mustafa Erdik
Bo
aziçi University
Kandilli Observatory and
Earthquake Research Institute
Department of Earthquake
Engineering
81220, Çengelköy, Istanbul,
Turkey
durukal{at}boun.edu.tr
(E.D.)
erdik{at}boun.edu.tr
(M.E.)
Strong-motion networks installed in the Hagia Sophia Museum and in the
Süleymaniye Mosque in Istanbul, Turkey, recorded a series of events
during the 17 August 1999, Kocaeli (Mw 7.4) and 12
November 1999, Düzce, Turkey (Mw 7.2) earthquakes and
during the following aftershock activity. The time-domain and frequency-domain
analysis of data presented in this article yielded the following results: On
the basis of the pre-1999 recordings in Hagia Sophia it was observed that the
modal frequencies tend to change with amplitude and duration of shaking. This
observation is supported by the recent data as well. Local problems were noted
in Hagia Sophia in the southwest main pier and possibly in Süleymaniye in
the west main arch. Significant vertical vibrations at the crowns of the east
and west main arches in Hagia Sophia are probably indicating locations where
most of the damage is to be expected during a major earthquake close to
Istanbul. A postearthquake, quick ambient vibration survey conducted in Hagia
Sophia showed a frequency drop in the first two modal vibrational frequencies
on the order of 4%5%, indicating the need for a comprehensive ambient
vibration study. Modal shapes and first-order estimates of modal damping of
the two structures have also been assessed.
Copyright © 2009 by Seismological Society of America